Portable communication terminals, typified by a cell phone, store user information or so, such as a telephone book, reception/transmission mail addresses, and mail texts, inside, and perform access, such as referring to the information or using it. When a portable communication terminal is lost, therefore, there is a risk that such confidential user information would be seen by a third person, and personal information or the like would be leaked.
A thin client approach is known which has all data stored in a server and accesses the server at the time of data access to prevent such a risk. Unexamined Japanese Patent Application KOKAI Publication No. 2002-24175 (Patent Document 1) discloses a thin client terminal.
Patent Document 1: Unexamined Japanese Patent Application KOKAI Publication No. 2002-24175